In computers, the utilisation of access often takes places to a few given memory addresses in comparison to remaining memory addresses. If the access time for thse given memory addresses is made as short as possible, the importance of the access time for the remaining memory addresses is reduced. Since this information accesible by means of these often used addresses are stored in a high speed buffer store or so-called "cache", the importance of memory access time is decreased. A condition for this is however that there is great probability that the sought-after information is in the rapid access memory. For every access not leading to data in the cache the sought-for data is written into the cache in the conventional solutions. This conventional method is usable if most of the accesses are to some few memory addresses or there is repeated access to a limited number of addresses, the limitation being determined by the size of the cache. If the mentioned limitations are not applicable, the cache will often lack the sought-after information, since new information has already been written into the cache. Thus, when access is attempted to some previously written-in information, it may have already been removed, and the cache contains mostly inappropriate information. The use of a conventional cache is described in Motorola's MC 68020 32-bit Microprocessor Uses's Manual, for example.